MoS₂/MoOCl₂范德瓦尔斯异质结构中的双曲激子-等离激元极化激元
Hyperbolic exciton-plasmon polaritons in MoS$_2$/MoOCl$_2$ van der Waals heterostructures
AI总结：
本文预测MoS₂/MoOCl₂异质结构可产生受多参数调控的双曲激子-等离激元极化激元，为可见光波段定向多模式极化激元工程提供无光刻平台。
AI中文摘要：
由激子与受限电磁模式强耦合形成的极化激元是新兴纳米光子技术的基础，但基于各向同性金属或光学微腔的平台对传播方向的调控能力有限。本文预测，面内双曲导体MoOCl₂上的单层MoS₂可支持受晶体学方向、薄片厚度和双曲模式阶次调控的双曲激子-等离激元极化激元。通过各向异性转移矩阵模型与耗散三能级哈密顿量耦合，我们得到MoOCl₂等离激元与MoS₂自旋-轨道分裂的A、B激子间依赖波矢的反交叉，产生低、中、上三支极化激元分支，耦合能分别为g_A=64.7 meV和g_B=61.2 meV。旋转面内波矢可调控等离激元-激子失谐，增加MoOCl₂厚度会激活高阶双曲法布里-珀罗模式，其耦合遵循近似的有效模式体积标度关系。当激子线宽高达50 meV时，强耦合仍可维持，且归一化光谱分辨率比保持在1以上。这些结果确立了MoS₂/MoOCl₂作为无光刻平台，可用于可见光波段的定向多模式激子-等离激元极化激元工程。
英文摘要：
Polaritons formed by strong coupling between excitons and confined electromagnetic modes underpin emerging nanophotonic technologies, yet platforms based on isotropic metals or optical microcavities provide limited control over propagation direction. Here we predict that monolayer MoS$_2$ on the in-plane hyperbolic conductor MoOCl$_2$ supports hyperbolic exciton-plasmon polaritons governed by crystallographic direction, slab thickness, and hyperbolic mode order. Using an anisotropic transfer-matrix model coupled to a dissipative three-level Hamiltonian, we obtain wavevector-dependent anticrossings between the MoOCl$_2$ plasmons and the spin-orbit-split A and B excitons of MoS$_2$, yielding lower, middle, and upper polariton branches with coupling energies $g_A$ = 64.7 meV and $g_B$ = 61.2 meV. Rotating the in-plane wavevector tunes the plasmon-exciton detuning, while increasing the MoOCl$_2$ thickness activates higher-order hyperbolic Fabry-Pérot modes. Their coupling follows an approximate effective-mode-volume scaling. Strong coupling persists for excitonic linewidths up to 50 meV, with the normalised spectral-resolution ratio remaining above unity. These results establish MoS$_2$/MoOCl$_2$ as a lithography-free platform for directional and multimode exciton-plasmon polariton engineering in the visible spectral range.
